Sandal upper



FIG. 1 is a perspective view of a sandal upper showing my new design;

FIG. 2 is a top view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a right side view thereof; and,

FIG. 6 is a perspective view of a second embodiment of FIG. 1.

The portion of the sandal shown in broken lines are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for sandal upper, as shown and described. 